A detective captain investigates a perfect secret room murder case, and the only suspect is a science fiction writer suffering from a rare "retrograde amnesia" - every day he wakes up, his memory will regress to a moment three days before the crime, and he firmly believes that he will be killed in the "future". The captain must piece together the truth from the chaotic memory fragments that the writer constantly resets and approaches the "moment of the crime", but desperately finds that all the evidence points to him. He seemed to be reading a "flashback novel" written by the murderer, and the ending was destined to be that he was the real murderer.
Concept: The enemy is time itself. The murderer took advantage of the misalignment of time perception to set up a psychological conspiracy that spanned the timeline. The deeper the detective investigates, the more it seems like he is completing an alibi for the murderer. The biggest fear is that all his resistance may have been written into the "murderer" script.